The recent electronic apparatus and equipment have been being developed under the concept of the needs and requirement of “thinner” and “lighter” and the high packing density of electronic components installed in the apparatus and equipment has been attempted. One of the major technologies to realize this high packing density is to use a flexible printed circuit cable (abbreviated as an FPC cable, hereinafter) which has characteristics of flexibility in the installation in various apparatuses and equipment.
Micro connecters to be used for the FPC cables have been enabling cable assembly in curved wiring and three dimensional installation with flexibility such as bending, twisting as well as satisfying the needs and requirements for “thinner” and “lighter” apparatuses and equipment. According to such feature, FPC cables have been adopted in the commercial products such as portable phones that require lightness and thinness as the devices. An example of the FPC micro connectors has been disclosed in the reference 1.
Reference 1:
Japanese laid open patent, 2000-048885
The FIGS. 7A to 7C show cross sectional views of the conventional connector 10. FIG. 7A shows the physical status before an FPC cable 30 is inserted to the connector 10. FIG. 7B shows the status after an FPC cable 30 is inserted to the connector 10 and FIG. 7C shows the status after an FPC cable 30 is clamped by a lever 22 set in the connector 10.
As shown in FIG. 7A, the housing 25 has an opening in the upper portion, side walls 26 in the both sides (a single side in the figure is drawn) and many slits (not shown in the figures) like as gaps between comb teeth. The housing, which is combined in a single unit with the slits to which many contacts 14 like as comb teeth are inserted therein, is attached to the printed circuit board 29.
The contacting piece 17 and the fixing piece 18 of the contact 14 clamps the salient 27 from the upper side and the lower side and the terminal portion 20 of the elastic support 15 of the contact 14 is substantially formed into a column shape. The lever 22 can rotate without interference around the terminal portion 20 which is formed into such substantially column shape at the terminal portion 20 of the elastic support 14. On the upper surface of the contacting piece 17, a contactor portion 19 which electrically contacts with the contacting terminal 31 formed the back surface of the FPC cable 30.
When the lever 22 is rotated in the arrow direction as shown in the FIG. 7B after the FPC cable 30 is set in the predetermined position on the housing 25, the FPC cable 30 is fixed in the physical status that the contacting terminal 31 (see FIG. 6) contacts with the contactor portion 19.
As shown in FIG. 8, the contacting terminals 31 are arranged in a pitch of 0.3 mm on back surface of the FPC cable 30 so that the contacting terminals 31 contact with the contactor portion 19 of the contacting piece 17 of the contact 14. For the manufacturing of the FPC micro connector, high precision press-forming and etching pattern forming have been used and the minimum forming pitch P can be as small as 0.1 mm. The final form of the contacting terminal 31 is rounded at the edges due to the etching process.
However, the quantity of the wires set in the FPC cable tends to increase in accordance with the requirement for the high-speed operation and the high integration of the devices in the recent booming and diffusion of portable telephones with built-in cameras, mobile communication services and internet communication. As the results, there is a problem that conventional FPC micro connectors cannot be accommodated in the limited inner room of the devices such as portable phones.
In order to satisfy the requirements for the application for portable phones, such that highly electrical insulation not to make shortage among wires even for narrowing of the adjacent terminals is maintained and therefore high reliability of terminal contact and high performance portable phones are satisfied, a large capacity FPC micro connector have been desired.
For this purpose, there is a strong demand for ultra-small FPC connectors that support the electronic devices which are in progress to multiple functionalities and high performances, a printed circuit board which has plurality of fine connection terminals and a FPC cable that has a high density contacting terminal.